Flash flood warnings in context: combining local knowledge and large-scale hydro-meteorological patterns Natural Hazards and Earth System Sciences DOI 10.5194/nhess-22-461-2022 2 May 2022 Local communities in northern Malawi have well-developed knowledge of the conditions leading to flash floods, spatially and temporally. Scientific analysis of catchment geomorphology and global reanalysis datasets corroborates this local knowledge, underlining the potential of these large-scale scientific datasets. Combining local knowledge with contemporary scientific datasets provides a common understanding of flash flood events, contributing to a more people-centred warning to flash floods. Read more
Modelling the volcanic ash plume from Eyjafjallajökull eruption (May 2010) over Europe: evaluation of the benefit of source term improvements and of the assimilation of aerosol measurements Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3731-2021 4 March 2022 Volcanic eruptions that spread out ash over large areas, like Eyjafjallajökull in 2010, may have huge economic consequences due to flight cancellations. In this article, we demonstrate the benefits of source term improvement and of data assimilation for quantifying volcanic ash concentrations. The work, which was supported by the EUNADICS-AV project, is the first one, to our knowledge, that demonstrates the benefit of the assimilation of ground-based lidar data over Europe during an eruption. Read more
Brief communication: Effective earthquake early warning systems: appropriate messaging and public awareness roles Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3243-2021 19 January 2022 Earthquake early warning systems (EEWSs) can help reduce losses, but their effectiveness depends on adequate public perception and understanding of EEWSs. This study examined the performance of the EEWS in China’s Sichuan Province during the 2019 Changning earthquake. We found a big gap existed between the EEWS’s message, the public’s perception of it, and their response. The study highlights the importance of gauging EEWS alert effectiveness and public participation for long-term resiliency. Read more
Assessment of direct economic losses of flood disasters based on spatial valuation of land use and quantification of vulnerabilities: a case study on the 2014 flood in Lishui city of China Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3161-2021 5 January 2022 Taking a single flood disaster in Lishui city as an example, a rapid and refined assessment of economic loss is studied and verified, which can effectively simulate the distribution of loss ratio and loss value. It includes the construction of land use type and value based on data fusion and an expert questionnaire survey, the fitting and calibration of vulnerability curves based on an existing database and disaster loss reporting, and estimation of loss ratio and loss value by spatial analysis. Read more
Evaluating integrated water management strategies to inform hydrological drought mitigation Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-3113-2021 27 December 2021 Managing water demand and supply during droughts is complex, as highly pressured human–water systems can overuse water sources to maintain water supply. We evaluated the impact of drought policies on water resources using a socio-hydrological model. For a range of hydrogeological conditions, we found that integrated drought policies reduce baseflow and groundwater droughts most if extra surface water is imported, reducing the pressure on water resources during droughts. Read more
An ensemble of state-of-the-art ash dispersion models: towards probabilistic forecasts to increase the resilience of air traffic against volcanic eruptions Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-2973-2021 6 December 2021 Past volcanic eruptions that spread out ash over large areas, like Eyjafjallajökull in 2010, forced the cancellation of thousands of flights and had huge economic consequences. In this article, an international team in the H2020 EU-funded EUNADICS-AV project has designed a probabilistic model approach to quantify ash concentrations. This approach is evaluated against measurements, and its potential use to mitigate the impact of future large-scale eruptions is discussed. Read more
The prediction of floods in Venice: methods, models and uncertainty (review article) Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-2679-2021 15 October 2021 The city of Venice relies crucially on a good storm surge forecast to protect its population and cultural heritage. In this paper, we provide a state-of-the-art review of storm surge forecasting, starting from examples in Europe and focusing on the Adriatic Sea and the Lagoon of Venice. We discuss the physics of storm surge, as well as the particular aspects of Venice and new techniques in storm surge modeling. We also give recommendations on what a future forecasting system should look like. Read more
Extreme floods of Venice: characteristics, dynamics, past and future evolution (review article) Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-2705-2021 13 October 2021 In this review we describe the factors leading to the extreme water heights producing the floods of Venice. We discuss the different contributions, their relative importance, and the resulting compound events. We highlight the role of relative sea level rise and the observed past and very likely future increase in extreme water heights, showing that they might be up to 160 % higher at the end of the 21st century than presently. Read more
Venice flooding and sea level: past evolution, present issues, and future projections (introduction to the special issue) Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-2633-2021 11 October 2021 Venice is an iconic place, and a paradigm of huge historical and cultural value is at risk. The threat posed by floods has dramatically increased in recent decades and is expected to continue to grow – and even accelerate – through this century. There is a need to better understand the future evolution of the relative sea level and its extremes and to develop adaptive planning strategies appropriate for present uncertainty, which might not be substantially reduced in the near future. Read more
Sea-level rise in Venice: historic and future trends (review article) Natural Hazards and Earth System Sciences DOI 10.5194/nhess-21-2643-2021 8 October 2021 Relative sea level in Venice rose by about 2.5 mm/year in the past 150 years due to the combined effect of subsidence and mean sea-level rise. We estimate the likely range of mean sea-level rise in Venice by 2100 due to climate changes to be between about 10 and 110 cm, with an improbable yet possible high-end scenario of about 170 cm. Projections of subsidence are not available, but historical evidence demonstrates that they can increase the hazard posed by climatically induced sea-level rise. Read more
